Reflective type color liquid crystal device and an electronic apparatus using this

• US 7,158,197 B2
• Filed: 11/24/2004
• Issued: 01/02/2007
• Est. Priority Date: 07/17/1995
• Status: Expired due to Fees

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Maeda, Tsuyoshi, Matsushima, Toshiharu, Okumura, Osamu, Okamoto, Eiji
• Primary Examiner(s): TON, MINH TOAN T
• Application Number:
  US10/995,176
• Publication Number:
  US 20050134766A1
• Time in Patent Office: 769 Days
• Field of Search: 349/106, 349/122, 349/138, 349/113, 430/7
• US Class Current: 349/106
• CPC Class Codes: G02B 5/201 in the form of arrays
• CPC Class Codes: G02B 5/22 Absorbing filters G02B5/201 - G02B5/208 take precedence
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 2201/52 RGB geometrical arrangements
• CPC Class Codes: G02F 2203/02 reflective
• CPC Class Codes: G02F 2203/66 Normally white display, i.e. the off state being white

Abstract

The invention comprises a pair of substrates having electrodes on the opposing inner surfaces and forming a matrix-patterned dot group, liquid crystals sandwiched between said substrates, at least two colors of color filters, at least one polarizing plate, and a reflective plate. Also, of said color filters, at least one color of color filters has a transmissivity of 50% or more for the light of all the wavelengths in the range of 450 nm to 660 nm.

Claims

1. A reflective type color liquid crystal device comprising:

a first electrode;

a second electrode opposing the first electrode;

a liquid crystal layer arranged between the first electrode and the second electrode;

a dot area formed at an overlapping portion of the first electrode and the second electrode, the dot area including a first section and a second section;

a color filter arranged in the first section; and

a layer arranged in the second section in which the color filter is not arranged, the layer being substantially transparent.

2. The reflective type color liquid crystal device according to claim 1, wherein the layer arranged in the second section also is formed in the areas between the dot areas.

3. The reflective type color liquid crystal device according to claim 1, a thickness of the color filter and a thickness of the layer arranged in the second section are different, wherein a difference of the thicknesses is 0.5 μ

m or less.

4. The reflective type color liquid crystal device according to claim 1, wherein the layer arranged in the second section is formed at substantially a same thickness as the color filter.

5. The reflective type color liquid crystal device according to claim 1, wherein the layer arranged in the second section includes acryl or polyimide.

6. An electronic apparatus comprising the reflective type color liquid crystal device according to claim 1.

7. The reflective type color liquid crystal device according to claim 1,

the second electrode including a plurality of second electrodes opposing the first electrode,

the dot area including a plurality of dot areas at overlapping portions between the first electrode and the second electrodes, the plurality of dot areas comprising a display face,

the color filter including a plurality of color filters in a one-to-one correspondence with the dot areas,

a surface area ratio of all the color filters to the entire display face being 15% or more.

8. The reflective type color liquid crystal device according to claim 7, the surface area ratio of all the color filters being 25% or more.

9. The reflective type color liquid crystal device according to claim 8, the surface area ratio of all the color filters being 45% or less.

10. The reflective type color liquid crystal device according to claim 8, the surface area ratio of all the color filters being 35% or less.

11. The reflective type color liquid crystal device according to claim 7, the surface area ratio of all the color filters being 45% or less.

12. The reflective type color liquid crystal device according to claim 7, the surface area ratio of all the color filters being 35% or less.

13. A reflective type color liquid crystal device comprising:

a first electrode;

a second electrode opposing the first electrode;

a liquid crystal layer arranged between the first electrode and the second electrode;

a plurality of dot areas arranged in a matrix, each of the dot areas including at least a first section and a second section, one of the dot areas formed at an overlapping portion of the first electrode and the second electrode;

a color filter arranged in the first section of the one dot area; and

a transparent layer arranged in the second section in which the color filter is not arranged.

14. The reflective type color liquid crystal device according to claim 13,

the color filter including a plurality of color filters in a one-to-one correspondence with the dot areas,

the color filter of the one dot area having a different color than the color filter arranged in an other dot area.

15. The reflective type color liquid crystal device according to claim 13,

the second electrode including a plurality of second electrodes opposing the first electrode, the plurality of dot areas formed at overlapping portions between the first electrode and the second electrodes,

the dot areas are light-variable areas which make a transmissivity of the liquid crystal layer variable by applying a voltage between the first electrode and the second electrodes.

16. The reflective type color liquid crystal device according to claim 15, color filters are provided only on a part of the light-variable areas in each dot area, each color filter partially formed substantially in a middle of one dot area.

17. The reflective type color liquid crystal device according to claim 13, wherein the transparent layer also is formed in the areas between the dot areas.

18. An electronic apparatus comprising the reflective type color liquid crystal device according to claim 17.

19. The reflective type color liquid crystal device according to claim 13, a thickness of the color filter and a thickness of the transparent layer are different, wherein a difference of the thicknesses is 0.5 μ

m or less.

20. The reflective type color liquid crystal device according to claim 13, wherein the transparent layer is formed at substantially a same thickness as the color filter.

21. The reflective type color liquid crystal device according to claim 13, wherein the transparent layer includes acryl or polyimide.

22. The reflective type color liquid crystal device according to claim 13, wherein a black mask is not provided in areas outside of each dot area.

23. An electronic apparatus comprising the reflective type color liquid crystal device according to claim 13.

24. The reflective type color liquid crystal device according to claim 13,

the second electrode including a plurality of second electrodes opposing the first electrode,

the plurality of dot areas formed at overlapping portions between the first electrode and the second electrodes, the plurality of dot areas comprising a display face,

the color filter including a plurality of color filters in a one-to-one correspondence with the dot areas,

a surface area ratio of all the color filters to the entire display face being 15% or more.

25. The reflective type color liquid crystal device according to claim 24, the surface area ratio of all the color filters being 45% or less.

26. The reflective type color liquid crystal device according to claim 24, the surface area ratio of all the color filters being 35% or less.

27. The reflective type color liquid crystal device according to claim 24, the surface area ratio of all the color filters being 25% or more.

28. The reflective type color liquid crystal device according to claim 27, the surface area ratio of all the color filters being 45% or less.

29. The reflective type color liquid crystal device according to claim 27, the surface area ratio of all the color filters being 35% or less.

30. A reflective type color liquid crystal device comprising:

a first electrode extending in a first plane;

a second electrode opposing the first electrode and extending in a second plane that is substantially parallel to the first plane;

a liquid crystal layer arranged between the first electrode and the second electrode;

a dot area formed at an overlapping portion of the first electrode and the second electrode, the dot area including a first section and a second section;

a color filter arranged in the first section; and

a layer arranged in the second section in which the color filter is not arranged, the layer being substantially transparent,

the color filter and the layer arranged in the second section are disposed adjacent to each other in a common plane that is substantially parallel to the first and second planes.

31. The reflective type color liquid crystal device according to claim 30, the layer arranged in the second section also is formed in areas between the dot areas and in the common plane.

32. The reflective type color liquid crystal device according to claim 30, a thickness of the color filter and a thickness of the layer arranged in the second section are different, wherein a difference of the thicknesses is 0.5 μ

m or less.

33. The reflective type color liquid crystal device according to claim 30, wherein the layer arranged in the second section is formed at substantially a same thickness as the color filter.

34. The reflective type color liquid crystal device according to claim 30, wherein the layer arranged in the second section includes acryl or polyimide.

35. An electronic apparatus comprising the reflective type color liquid crystal device according to claim 30.

36. The reflective type color liquid crystal device according to claim 30,

the second electrode including a plurality of second electrodes opposing the first electrode,

the dot area including a plurality of dot areas at overlapping portions between the first electrode and the second electrodes, the plurality of dot areas comprising a display face,

the color filter including a plurality of color filters in a one-to-one correspondence with the dot areas,

a surface area ratio of all the color filters to the entire display face being 15% or more.

37. The reflective type color liquid crystal device according to claim 36, the surface area ratio of all the color filters being 25% or more.

38. The reflective type color liquid crystal device according to claim 37, the surface area ratio of all the color filters being 45% or less.

39. The reflective type color liquid crystal device according to claim 37, the surface area ratio of all the color filters being 35% or less.

40. The reflective type color liquid crystal device according to claim 36, the surface area ratio of all the color filters being 45% or less.

41. The reflective type color liquid crystal device according to claim 36, the surface area ratio of all the color filters being 35% or less.